It is possible to draw at first from a vase. If it is so more convenient to you, begin with it. I will begin with the lowermost rose, we start drawing it from the middle and gradually we increase petals.
It is slightly above and more to the right we draw the second rose, also we begin with the middle.
From above we draw the third bud of a rose.
Between them draw branches with leaves.
Still draw leaves and approximately on a half of the lower rose lower a small straight line down, then within leaves lower the same straight line. It will be the top part of a vase. Below a hyphen note height of a vase and draw its outline.
There is a lesson how to draw a rose in a pot, shading is in more detail considered there. Make shading, changing pressing a pencil, for tone change. It is possible after that to shade as in a lesson a willow in a vase.
Leaves it is shaded very dark with tone, having taken softer a pencil. And also we apply light shading on petals of roses.
For more beautiful effect, it is possible to make a background in the form of diagonal lines. Drawing a bouquet of roses or a rose in a vase is ready.